#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>

int main() {
	int i = 0;
	int x = -1;
	double sum = 1;
	for (i = 2; i <= 100; i++) {
		sum += 1.0 / (x * i);
	}
	printf("%lf\n", sum);
	return 0;
}